Add Heading hereThe Cyclo Standard touring derailleur
Parts Diagram from 1955
This early derailleur design originated from France - Raimond's 1923 device - the Cyclo Standard was the definitive touring derailleur for many decades. The design of the mechanism was said to have been inspired by machine guns that Raimond examined during the First World War. In 1932 the British Cyclo Gear Company was established by Albert Raimond and Louis Camillis, and the Cyclo Standard was its first product.
Do view the other links of the images in the above link. Fascinating to have owned one.